Hi Nancy,
We've been traveling with our three kids since the first was was an infant, and here is where we have gone: Door County, WI; Pittsburgh, PA; Adrinodack Mountains, NY; Chattanooga, TN; St. Louis, MO; Minneapolis, MN; Wisconsin Dells, WI; and a trip around Lake Michigan (WI and MI). All of the trips have been special in their own way, but my kid-friendly favorites have been St. Louis, Minneapolis, and the trip around Lake Michigan - Mackinac Island and Traverse City, MI, and Green Bay, WI were especially fun! This year we are headed to the Smoky Mountains (Gatlinburg, TN), which looks like a fun destination as well, and only a 10 hour drive or so. 10 hours is a bit far for my three kids (now 7, 5, and 2), but if you break the drive up into two days, and stop in Louisville or Indianapolis, with a quick trip to a zoo or kids museum, it makes the drive much easier with the wee ones. Good luck vacation planning, and hope you all have loads of fun!